Suspension math you can check
Free calculators for off-road builders, from first sketch to final tack welds. The geometry is checked against the well-known Barcroft link spreadsheets, cell by cell, in Excel.
3-Link Suspension
Solid axle with a Panhard bar: anti-squat, roll center, link forces and tube strength, through the full range of travel.
Suspension4-Link Suspension
Triangulated 4-link: anti-squat, roll axis, link forces and tube strength, through the full range of travel.
SuspensionCoilover
Wheel travel, motion ratio, wheel rate and ride frequency from shock length and angle.
DrivetrainCrawl Ratio
Crawl ratio, speed in every gear, tire-size correction and an axle-shaft check.
How the numbers are checked
The link calculators reproduce the 3-link and 4-link spreadsheets by Dan Barcroft, Greg Blanchette and Chris Macock. More than 700 test cases are run through those spreadsheets in Excel, and the results are compared value by value. Where a spreadsheet is wrong, for example in its link-force formula or its travel solution for some layouts, these calculators use the correct physics instead. The reference page explains every difference.
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